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A strip of filter paper dissolved in ethereal solution containing p-dimethylamino benzaldehyde and hydroquinone and then moistened with a 30% solution of trichloroacetic acid in isopropanol produces blue-violet colour in the presence of pyrolytic vapours of rubbers A and B. Which of the following pair represent rubbers A and B?

A strip of filter paper dissolved in ethereal solution containing p-dimethylamino benzaldehyde and hydroquinone and then moistened with a 30% solution of trichloroacetic acid in isopropanol produces blue-violet colour in the presence of pyrolytic vapours of rubbers A and B. Which of the following pair represent rubbers A and B? Correct Answer natural rubber and butyl rubber

The pyrolytic vapours of natural rubber and butyl rubber both produce deep-blue or blue-violet colour to the paper.

Related Questions

Which of the following rubbers turn the filter paper in ethereal solution containing p-dimethylamino benzaldehyde and hydroquinone and then moistened with a 30% solution of trichloroacetic acid in isopropanol grey with a yellow tinge?
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